JP2009544178A - Signal acquisition for wireless communication systems - Google Patents

Abstract

  Systems and methods are described that facilitate signal acquisition in a wireless communication system with one or more frequency carriers corresponding to a portion of deployed bandwidth in a wireless communication environment. By communicating with a carrier that includes only a portion of the overall system bandwidth, the channel used for communication on one carrier may be less distributed than the channel used for communication over the entire bandwidth. Good. Thus, the amount of transmit power required for devices in the system can be reduced. Further, the carriers may be partitioned from the deployed system bandwidth so that each carrier is large enough to minimize the effect of fading on the component frequency response, thereby further optimizing system performance. .

Description

  The present invention relates generally to wireless communication, and more particularly to techniques for signal acquisition in a wireless communication system.

  Wireless communication systems have become a powerful means of communicating with the majority of people around the world. In addition, wireless communication devices such as cell phones are becoming smaller and more powerful to meet consumer needs and to improve portability and convenience. This increase in processing capacity has led to an increase in required performance of the wireless network transmission system. However, such a system is usually not as easily updated as a portable device with which it communicates. As mobile device capabilities expand, it can be difficult to maintain an old wireless network system in a manner that facilitates fully developing new and improved wireless device capabilities.

  For example, wireless communication systems typically generate transmission resources in the form of channels from system deployment bandwidth. Enforce sufficient system performance, such as signal acquisition performance, in wireless communication systems when large bandwidth is deployed in the network, as in many networks that support newer, more powerful mobile devices It has been difficult to do so far. For example, the frequency response of a component in a system with a large bandwidth can vary greatly across the bandwidth due to fading and / or other factors. Usually this change in frequency response requires the creation of a wider channel. However, wider channels are often distributed, which can greatly increase the amount of transmit power required for communication on a given channel.

Summary of the Invention

  The following presents a simplified summary of an embodiment in order to provide a basic understanding of the disclosed embodiment. This summary is not an exhaustive overview of all intended embodiments, and is not intended to identify basic or critical elements or to delineate the scope of the embodiments. Its sole purpose is to present some concepts of the disclosed embodiments in a simplified form as a prelude to the more detailed description that is presented later.

  The described embodiments mitigate the above problem by dividing the bandwidth deployed for the wireless communication system into multiple carriers. Each device in the system can perform signal acquisition or communicate in other ways using a portion of the deployed bandwidth corresponding to one or more carriers. By communicating with a carrier that includes only a portion of the total system bandwidth, the channel used for communication on one carrier may be less distributed than the channel used for communication across the entire bandwidth. Good. Accordingly, the amount of transmission power required for devices in the system can be reduced. In addition, the carriers are divided from the deployed system bandwidth so that each carrier is large enough to minimize the effect of fading on the component frequency response, thereby further optimizing system performance. Can be made to do.

  According to one aspect, provided herein is a method for generating and transmitting acquisition information in a wireless communication system. The method comprises generating a plurality of symbols of the acquired signal. Further, the method may include allocating transmissions of the acquired signal to a number of subcarriers equal to all or less than all of one or more carrier bandwidths.

  Another aspect relates to a wireless communications apparatus that may include a memory that stores data regarding a plurality of carriers corresponding to a substantially non-overlapping portion of an acquired signal and available system bandwidth. The wireless communications apparatus may further include a processor configured to assign the acquired signal to all or a portion of one or more of the plurality of carriers.

  Yet another aspect relates to an apparatus that facilitates signal acquisition in a wireless communication network. The apparatus may comprise means for dividing available system bandwidth into a plurality of carriers. Further, the apparatus may include means for transmitting the acquired information to the terminal using one or more of the plurality of carriers.

  Yet another aspect relates to a computer-readable medium having stored thereon computer-executable instructions for generating and transmitting information for acquisition in a wireless communication environment. The instructions may comprise dividing the available system bandwidth into a plurality of carriers each having a bandwidth equal to a plurality of subcarriers and a portion of the system bandwidth. Further, the instructions may include generating a plurality of symbols for the acquisition signal. Further, the instructions may include transmitting the acquisition signal on some of one or more subcarriers in at least one of the plurality of carriers.

  According to other aspects, provided is a processor capable of executing computer-executable instructions for transmitting acquisition information. The instructions may comprise generating a first acquisition signal and a second acquisition signal. Further, the instructions may comprise transmitting a first acquisition signal to the first access terminal on a carrier with a portion of the available system bandwidth. Further, the instructions may include transmitting a second acquisition signal to the second access terminal on a carrier with a portion of the available system bandwidth.

  According to yet another aspect, provided herein is a method for obtaining information for communication in a wireless communication system. The method may comprise attempting to detect the acquired signal on at least two carriers, each with one or more subcarriers and a portion of the usable system bandwidth. Further, the method may include determining a future carrier on which information is communicated by the access point based at least in part on the carrier on which the acquired signal is detected.

  Another aspect relates to a wireless communication apparatus that may include a memory that stores data related to a plurality of carriers. The wireless communications apparatus is also configured to attempt to detect acquired signals on multiple carriers and to determine future carriers on which information is communicated by the sector based at least in part on the carriers on which the acquired signals are detected Processor may be included.

  Yet another aspect relates to an apparatus that facilitates signal acquisition in a wireless communication network, wherein the apparatus can comprise means for detecting an acquired signal in a system bandwidth corresponding to a plurality of carriers. The apparatus may further comprise means for determining a carrier for communication with the access point based at least in part on the carrier on which the acquired signal is detected.

  Yet another aspect relates to a computer-readable medium that stores computer-executable instructions for obtaining information for communication in a wireless communication environment. The instructions may include detecting an acquisition signal transmitted by the access point over a bandwidth equal to at least two carriers. Further, the instructions may include determining a carrier for communication with the access point based at least in part on the acquired signal.

  According to other aspects, a processor that can execute computer-executable instructions for communication in a wireless communication system is described herein. The instructions may comprise receiving an acquisition signal transmitted from a sector of the wireless communication system. Further, the instructions may comprise determining one or more carriers for communication with the sector based at least in part on the carrier on which the acquisition signal was received. Further, the instructions may comprise communicating with the sector, at least in part, using one or more carriers determined for communication.

  To the accomplishment of the above and related ends, one or more embodiments comprise the features that are fully described below and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative aspects of the disclosed embodiments. However, these aspects only illustrate some of the various ways in which the principles of the various embodiments may be used. Furthermore, the disclosed embodiments are intended to include all such aspects and their equivalents.

Detailed description

  Various embodiments are described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are presented in order to provide a thorough understanding of one or more aspects. However, it will be apparent that such embodiments may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing one or more embodiments.

  As used herein, the terms "component", "module", "system", etc. refer to hardware, firmware, a combination of hardware and software, software, or computer-related such as running software Is intended to mean the entity of For example, a component may be, but is not limited to being, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, and / or a computer. By way of illustration, both an application running on a computing device and the computing device can be a component. One or more components may be present in the process and / or thread of execution, one component may be localized on one computer, and / or two or It may be distributed among more computers. In addition, these components can execute from various computer readable media having various data structures stored thereon. These components interact with other components across a network, such as the Internet, such as a signal having one or more data packets (eg, in a local system, distributed system and / or with other systems through that signal) It may be communicated by local and / or remote processes, such as by data from one component.

  Moreover, various embodiments are described herein in connection with a wireless terminal and / or a base station. A wireless terminal may refer to a device that provides voice and / or data connectivity to a user. The wireless terminal may be connected to a computing device such as a laptop computer or a desktop computer, or may be a self-contained device such as a portable information device (PDA). A wireless terminal may also be referred to as a system, subscriber unit, subscriber station, mobile station, mobile remote station, access point, remote terminal, access terminal, user terminal, user agent, user device, or user equipment. . Wireless terminals include subscriber stations, wireless devices, mobile phones, PCS phones, cordless phones, session initiation protocol (SIP) phones, wireless local loops, personal digital assistants (PDAs), and handheld devices with wireless connectivity capabilities Or another processing device connected to the wireless modem. A base station (eg, access point) may refer to a device in an access network that communicates with a wireless terminal by way of an air-interface through one or more sectors. The base station acts as a router between the wireless terminal and the rest of the access network, which may include an Internet Protocol (IP) network, by converting received radio interface frames into IP packets . The base station coordinates the management of attributes for the radio interface.

  Moreover, various aspects or features described herein may be implemented as a manufacturing method, a manufacturing apparatus, or a manufactured article using standard programming and / or engineering techniques. The term “article of manufacture” as used herein is intended to encompass a computer program accessible from any computer-readable device, carrier, or media. For example, computer readable media include magnetic storage (eg, hard disk, floppy disk, magnetic strip), optical disk (eg, compact disk (CD), digital versatile disk (DVD), smart card, and flash memory. Devices (eg, cards, sticks, key drives) may be included, but are not limited to them.

  Various embodiments will be presented in terms of systems that can include multiple devices, components, modules, and the like. These various systems may include additional devices, components, modules, etc. and / or may not include all of the devices, components, modules, etc. discussed in connection with the drawings. It should be understood and recognized. A combination of these approaches may be used.

  Referring to the drawings, FIG. 1 is an illustration of a wireless multiple-access communication system 100 in accordance with various aspects. In one example, the wireless multiple-access communication system 100 includes multiple base stations 110 and multiple terminals 120. Further, one or more stations 110 can communicate with one or more terminals 120. By way of non-limiting example, base station 110 may be an access point, Node B, and / or other suitable network entity. Each base station 110 provides communication coverage 102 for a particular geographic region. As used herein and generally in the art, the term “cell” refers to the base station 110 and / or its coverage area depending on the context in which the term is used. (Coverage area) 102.

  To improve system capacity, the coverage area 102 corresponding to the base station 110 may be divided into a number of smaller areas (eg, areas 104a, 104b, and 104c). Each of these small areas 104a, 104b, and 104c may be served by a respective base transceiver subsystem (BTS, not shown). As used herein and generally in the art, the term “sector” refers to a BTS and / or its coverage area, depending on the context in which the term is used. be able to. In one example, sector 104 in cell 102 may be formed by a group of antennas (not shown) at base station 110, each group antenna communicating with terminal 120 in a portion of cell 102. Involved in. For example, base station 110 serving cell 102a may have a first antenna group corresponding to sector 104a, a second antenna group corresponding to sector 104b, and a third antenna group corresponding to sector 104c. You may have. However, it should be appreciated that the various aspects disclosed herein may be used in systems having sectorized and / or non-sectorized cells. Moreover, all suitable wireless communication networks having any number of sectorized and / or non-sectorized cells are intended to be within the scope of the claims appended hereto. Should be recognized. For simplicity, the term “base station” as used herein may refer to both a station serving a sector and a station serving a cell. .

  According to one aspect, the terminals 120 can be distributed throughout the system 100. Each terminal 120 may be fixed or movable. By way of non-limiting example, terminal 120 may be an access terminal (AT), a mobile station, user equipment, a subscriber station, and / or other suitable network entity. Terminal 120 may be a wireless device, a cellular phone, a personal digital assistant (PDA), a wireless modem, a handheld device, or other suitable device. Further, terminal 120 may be in communication with any number of base stations 110 at any given time, or may not be in communication with base station 110.

  In other instances, the system 100 is centralized by using a system controller 130 that can be coupled to one or more base stations 110 and can provide coordination and control for the base stations 110. A centralized architecture can be used. According to other aspects, system controller 130 may be a single network entity or a collection of network entities. Further, the system 100 may utilize a distributed architecture to cause the base stations 110 to communicate with each other as needed. In one example, system controller 130 may additionally include one or more connections to multiple networks. These networks provide information to and / or from the terminal 120 that communicates with the Internet, other packet-based networks, and / or one or more base stations 110 in the system 100. Possible circuit switched voice networks. In other examples, system controller 130 may include or be coupled to a scheduler (not shown) that schedules transmissions to and / or from terminal 120. Alternatively, the scheduler may reside in each individual cell, each sector 104, or a combination thereof.

  According to one aspect, each sector 104 can operate utilizing one or more of multiple carriers. In one example, each carrier is a portion of the large bandwidth in which system 100 can operate. Alternatively, each carrier may be part of the system bandwidth that can be used for communication. According to other aspects, a single sector 104 may utilize one or more carriers and is scheduled for each of the carriers utilized by sector 104 at any given time interval. Multiple terminals 120 may be included (eg, physical layer frame or superframe).

  Furthermore, one or more terminals 120 can be scheduled on multiple carriers simultaneously depending on the capabilities of each terminal 120. In one example, these capabilities may be included in pre-arranged session information, or may be part of the session information generated when terminal 120 is attempting to obtain communication. The session information may comprise a session identification token that may be generated by querying the terminal 120 or by determining the capabilities of the terminal 120 through its transmission. Alternatively, these capabilities may be part of the identification information transmitted by terminal 120. The capabilities of terminal 120 may be established according to any other suitable approach.

  According to another aspect, the acquisition signal may be provided only for one carrier of a given superframe. Furthermore, the acquisition signal may be provided in a superframe preamble. The carrier used for the acquisition signal may change over time based on, for example, a hop sequence. By reducing the acquisition signal to one carrier, the dispersion effects encountered for acquisition by terminal 120 may be reduced. Further, in examples where each base station 110 can have a different hop sequence or pattern, the likelihood of acquisition signal collisions is reduced and the acquisition capability by the terminal 120 is improved. Further, although the system 100 is illustrated as including a physical sector 104, it should be appreciated that other approaches may be utilized. For example, multiple fixed “beams” that can each cover different areas of a cell 102 may be utilized in place of or in combination with physical sector 104. Such an approach is a concurrent US patent filed on 27 October 2005 entitled “ADAPTIVE SECTORIZATION IN CELLULAR SYSTEMS”, which is incorporated herein by reference in its entirety. Illustrated and disclosed in application Ser. No. 11 / 269,895.

FIG. 2 is a block diagram of a system that facilitates signal acquisition in a wireless communication environment in accordance with various aspects described herein. In one example, system 200 includes one access point 210 and multiple access terminals 220. Although not shown in system 200 for brevity, system 200 may include multiple access points 210. According to one aspect, the access point 210 can include one or more antenna groups that can each include one or more antennas 214 and / or 216 that can communicate with one or more access terminals 220. 212 may be included. For example, as shown in system 220, antenna group 212 ₁ includes R antennas 214 and antenna group 212 _N includes T antennas 216. In one instance, the access point 210 can serve one cell (eg, one cell 102), and each antenna group 212 in the access point 210 can serve one sector in that cell. (E.g., sector 104).

  According to another aspect, the bandwidth available for communication in system 200 can be divided into multiple carriers. Each access point 210 and / or each antenna group 212 at one access point 210 can utilize one or more of the carriers to communicate with the access terminal 220. This communication may include, for example, transmission of one or more acquisition pilots and / or broadcast channels to the access terminal. Each carrier is available at each access point 210 or each access point 210 can use a subset of the available carriers. Similarly, each antenna group 212 at the access point 210 can use all of the carriers provided by the access point 210 or a subset of those carriers. The carriers utilized in system 200 may be unique (unique) to each access point 210 and / or antenna group 212 within one access point 210, or more than one access point 210 and (Or) The antenna group 212 may use a specific carrier.

  According to other aspects, the acquired signals, broadcast channels and / or other communications transmitted by each antenna 214 and 216 at access point 210 may be transmitted by one or more access terminals 220 via corresponding antennas 222. Can be received via. Although only one antenna 222 is shown for each access terminal 220, it should be appreciated that each access terminal 220 may have any number of antennas 222. Further, each antenna 222 in one access terminal 220 is used for communication with one or more access points 210, antenna groups 212 within one access point 210, and / or other access terminals 220. Can be done. In one example, each access terminal 220 can receive an acquisition signal from one access point 210 on one carrier utilized by system 200. The carrier on which the acquisition signal is received by access terminal 220 may be predetermined, or one or more access terminals 220 may monitor over the entire available bandwidth of system 200 for the acquisition signal. May be.

In other instances, each access terminal 220 receives an assignment for one or more carriers to be used for communication with one access point 210 or antenna group 212 within one access point 210. Can do. As a non-limiting example, an access terminal 220 with limited ability to communicate over a large band is assigned to a single carrier, while an access terminal 220 with greater ability to communicate over a larger band can be multiple carriers. The assignment may be made so that it can be assigned to According to one aspect, this assignment may include the carrier for which the acquisition signal was received by each access terminal 220 and / or one or more other carriers. Further, each carrier may be utilized simultaneously by one or more access terminals 220 at the same time. For example, as shown by system 200, access terminal 220 _K-1 may be assigned to carrier N, access terminal 220 _K may also be assigned to carrier N, and further May be assigned to two carriers N + R. According to one aspect, the effect of channel dispersion within the system 200 can be reduced by communicating with a cailer that is generally smaller than the overall bandwidth of the system 200. This reduces the transmission power required for each access point 210 and / or access terminal 220, thereby increasing the efficiency of each access point 220, and / or the battery of each access terminal 220. Save life. Further, the system bandwidth may be partitioned such that each carrier is large enough to minimize the effects of fading and other similar factors on system performance. As a specific, non-limiting example, system 200 may utilize a 20 MHz bandwidth, and each carrier may include 5 MHz of the total bandwidth. However, this example only illustrates one possible system bandwidth and carrier splitting that can be used in system 200, and any other suitable system bandwidth and / or carrier splitting can also be used. It should be recognized.

  FIG. 3A shows an exemplary superframe structure for a multiple access wireless communication system (eg, system 100) that utilizes frequency division duplexing. In one example, a superframe preamble 312 is transmitted at the beginning of each superframe 310. Superframe preamble 312 may span one carrier or a portion thereof. Further, each superframe preamble 312 may hop for each superframe 310, a predetermined number of superframes 310, a fixed time interval, or other suitable interval. Further, each superframe preamble 312 may hop according to a hop sequence or pattern that may be determined based on an identification for one access point (eg, access point 110). For example, the access point identification may be a pseudo noise (PN) sequence from which the access terminal (eg, terminal 120) can determine a hop pattern or sequence for the superframe 310. The access terminal then determines a carrier to be associated with the superframe preamble 312 in the next superframe 310 and a carrier associated with the superframe preamble 312 in the last superframe 310 based on the access point identification. be able to. Further, although superframe 310 has been shown as a forward link (FL) superframe, it should be appreciated that superframe 310 may alternatively be a reverse link superframe. is there.

  In one example, the transmission can be divided into units of superframes 310 each consisting of a superframe preamble 312 followed by a series of frames 314. In FDD structure 302, reverse link transmission and forward link transmission may occupy different frequencies so that transmissions on the forward and reverse links are substantially non-overlapping on any frequency subcarrier. Good. In another example, superframe preamble 312 can include a pilot channel that can include pilots that can be used for channel estimation by an access terminal. Further, the superframe preamble 312 includes a broadcast channel that includes configuration information that can be used by one access terminal (eg, terminal 120) to demodulate the information contained in the forward link frame 314. Can be included. Additionally and / or alternatively, the superframe preamble 312 includes acquisition information, power control information, and / or offset information, such as timing and other information sufficient for the access terminal to communicate. You may go out. Accordingly, the superframe preamble 312 includes one or more common pilot channels, broadcast channels, acquisition pilot channels, other sector interference channels, and / or other suitable channels. be able to.

  In other examples, the superframe preamble 312 includes a pilot channel for synchronization and sector ID acquisition, a first broadcast channel that carries static deployment parameters and system time, and / or ) It may include a second broadcast channel carrying quasi-static sector parameters. In one example, the quasi-static sector parameters carried by the second broadcast channel are the forward link configuration in the odd superframe 310 and the quick paging channel 310 in the even superframe 310. Can be related to. Further, the parameters may include auxiliary dynamic parameters such as sector loading. In other examples, the first broadcast channel can be coded with respect to multiple superframes 310 and the second broadcast channel can be coded with respect to a single superframe 310.

  According to one aspect, the superframe preamble 312 may include one or more symbols, such as OFDM symbols, and one or more symbols in the superframe preamble 312 may be a sector ( For example, it may hop according to a hop sequence or pattern coordinated between sectors 104). For example, a hop sequence or scheduling scheme that is common to one set of sectors of the network or all of the sectors may be used. According to other aspects, the first broadcast channel, the second broadcast channel, or both the first and second broadcast channels may hop in a given superframe 310.

  In other examples, the total bandwidth for the system may be divided into one or more carriers, and each carrier may be divided into multiple frequency subcarriers or tones. For each superframe 310 in each sector, one of the carriers can be used to populate the superframe preamble 312 corresponding to each superframe 310. Further, a re-use factor K may be applied to the tones that make up the superframe preamble 312. Thus, for a given superframe 310 (represented here as SFidx) in a given sector (represented here as PilotPN), it has a broadcast channel, another channel, and / or an index k. The symbol of the superframe preamble 312 for the superframe 310 provided by the carrier can be defined as follows: However, 0 ≦ k ≦ K.

k = PilotPhase mod K
PilotPhase = (PilotPN + Sfidx) mod N (1)
PilotPN and PilotPhase may be identity scrambling indices for a given sector or other suitable coefficient used to identify a given sector, and N is PilotPhase. Corresponds to a predetermined maximum value. In another example, PilotPN and PilotPhase may scramble one or more pilot signals transmitted by a given sector in superframe preamble 312 to allow the access terminal to identify the sector. Can be used.

  According to another aspect, when multiple sectors use a shared spectrum for the superframe preamble 312, the paging is not performed in the superframe preamble 312. For example, when a large number of sectors share a subcarrier including the superframe preamble 312, paging may not be performed. Further, if PilotPN1 and PilotNP2 are each identification of different sectors, hopping can be kept orthogonal by maintaining the following equation:

(PilotPN ₁ ― PilotPN ₂ ) mod K ≠ 0 (2)
Accordingly, different sectors in the system, ie sectors with different values of PilotPN mod K, will utilize different carriers. As a specific, non-limiting example, by selecting a reuse factor of K = 8 and dividing the available system bandwidth into 8 subsets, 7-sector frequency reuse is based on equation (1). Can be achieved. Frequency planning is coordinated with PilotPN index planning so that a subset of bandwidth satisfying PilotPN mod 7 = 0 is not allocated and 7-sector frequency reuse is performed for the remaining 7 sectors. Can be done. In another non-limiting example, a 7-sector frequency re-transmission is selected by selecting a reuse factor of K = 7 and dividing the available system bandwidth into seven subsets (each subset can be subsequently allocated). Use can be achieved according to equation (1). In this example, the value of N corresponding to the maximum value of PilotPhase may be selected as a multiple of 7. In one particular non-limiting example, N may be selected as 511.

  Further, after the superframe preamble 312, there is a sequence of frames 314. Each frame 314 may consist of a uniform or non-uniform number of OFDM and a uniform or non-uniform number of subcarriers that can be utilized simultaneously for transmission. As a specific, non-limiting example, the superframe preamble 312 is composed of 32 OFDM symbols and is followed by 48 frames 314, where each frame 314 can be composed of 8 OFDM symbols. is there. In another non-limiting example, each superframe preamble 312 is composed of 16 frames and can be followed by 48 frames 314 that are 8 OFDM symbols long. Further, each frame 314 can operate according to a symbol rate hopping mode, and can transmit one or more consecutive OFDM to terminals on the forward or reverse link. A symbol is assigned. Alternatively, each frame 314 can operate according to a block hopping mode 320, and the terminal can hop within an OFDM block. In both block hopping mode 320 and symbol rate hopping mode 322, the block or OFDM symbol may or may not hop between frames 314.

  According to another aspect, the superframe 310 may not utilize the superframe preamble 312. In one alternative, the preamble may be provided for one or more frames 314 that contain equivalent information for the superframe preamble 312. In other alternatives, a broadcast control channel may be utilized to include some or all of the superframe preamble 312 information. Other information may additionally be included in the preamble or frame 314 control channel.

  FIG. 3B shows an exemplary superframe structure 304 for a multiple access wireless communication system utilizing time division multiplexing (TDD). In one example, superframe preamble 312 can be transmitted at the beginning of each superframe that is substantially similar in structure and performance to superframe 312 in FDD structure 302. In accordance with one aspect, each superframe preamble 312 in the TDD structure 304 can be followed by a sequence of forward link frames 314 and reverse link frames 316. Forward link frame 314 and reverse so that a predetermined number of forward link frames 314 are continuously transmitted before allowing a predetermined number of reverse link frames 316 to be transmitted. The link frame 316 may be divided in time. As shown in superframe structure 304, forward link superframe 310 will experience mute time upon transmission of one or more reverse link frames 316. Similarly, it should be appreciated that the reverse link superframe will experience silence during transmission of the forward link frame 314. Further, any number of forward link frames 314 and any number of reverse link frames 316 may be transmitted consecutively in superframe structure 304, and the number of frames may be within a given superframe. It should be appreciated that it may vary in or between superframes.

  Further, each forward link frame 314 is a uniform or non-uniform number of OFDM symbols and a uniform or non-uniform number that can be utilized simultaneously for transmission in a manner similar to frames 314 in the FDD structure 302. Of subcarriers. In one example, each forward link frame 314 operates according to a symbol rate hopping mode 322 in which one or more non-consecutive OFDM symbols are assigned to terminals on the forward or reverse link. be able to. Alternatively, each forward link frame 314 may operate according to a block hopping mode 320 that allows the terminal to hop within a block of OFDM symbols. In both block hopping mode 320 and symbol rate hopping mode 322, symbols may or may not hop between forward link frames 314.

  According to one aspect, the superframe 310 may not utilize the superframe preamble 312. In one alternative, the preamble may be provided for one or more frames 314 that contain equivalent information for the superframe preamble 312. In other alternatives, a broadcast control channel may be utilized to include some or all of the superframe preamble 312. Other information may additionally be included in the preamble or control channel of the frame 314.

  FIG. 4 is an example channel structure for a multiple access wireless communication system (eg, system 100) in accordance with various aspects. In one example, bandwidth 400 may be available for communication with system design parameters. Furthermore, the bandwidth 400 may include several carriers 402. Each carrier 402 may include one or more forward link frames 404 and reverse link frames 408, each of which is one or more superframes (eg, superframe 310 ).

  According to one aspect, each forward link frame 404 of each carrier 402 can include one or more control channels 406. Illustratively, each of the control channels 406 is associated with each access terminal (eg, terminal 120) in the same or different system for acquisition acknowledgments (acquisitions; acknowledgements), broadcast, multicast, and unicast message types. ), Forward link assignment for each access terminal in the system, reverse link power control for each access terminal in the system, functions related to reverse link acknowledgments, and (Or) other suitable functions may be included. It should be appreciated that the control channel 406 on each of the carriers 402 can provide uniform or non-uniform information to support the same or different functions. Further, the control channel 406 may hop within each forward link frame 404 according to a hopping sequence that may or may not be uniform between carriers 402. Further, the hopping sequence for each control channel 406 may be the same as or different from the hopping sequence assigned to the data channel (not shown) in each forward link frame 404.

  According to other aspects, each reverse link frame 408 can include a number of reverse link transmissions 412-430 from an access terminal. Although each reverse link transmission 412-430 in reverse link frame 408 is illustrated as a block, ie, a group of consecutive OFDM symbols, each transmission 412-430 alternatively provides symbol rate hopping. It should be appreciated that each transmission 412-430 may correspond to a discontinuous symbol block. Further, each reverse link frame 408 may include one or more reverse link control channels 440. Illustratively, the reverse link control channel 440 includes a feedback channel, a pilot channel for reverse link channel evaluation, an acknowledgment channel that can be included in the reverse link transmissions 412-430, and ( Or) other suitable channels may be included. Further, each reverse link control channel 440 includes, for example, forward link and reverse link resource requirements, channel information (eg, channel quality information (CQI) for different types of transmissions), channel, and channel by each access terminal in the system. Information regarding pilot related functions from an access terminal that may be used by an access point (eg, base station) for evaluation purposes, and / or other suitable functions may be provided. In one example, the reverse link control channel 440 may hop in each reverse link frame 408 according to a hopping sequence that may or may not be uniform between carriers 402. Further, the hopping sequence for each reverse link control channel 440 may be the same as or different from the hopping sequence assigned to the data channel (not shown) in each link frame 408.

  According to one aspect, one user may multiplex users for the reverse link control channel 440 to separate each user and / or each unique type of information transmitted on the reverse link control channel 440. Or, more orthogonal codes, scrambling sequences, or similar codes and / or sequences may be utilized. In one example, the orthogonal code may be user specific. Additionally and / or alternatively, orthogonal codes may be assigned by the access point to each terminal for each communication session or shorter period (eg, each superframe 310).

  In one example, several access terminals are assigned to a single carrier 402 and each forward link transmission sent to one terminal in one superframe or multiple frames of a superframe is assigned to the same carrier. . Thus, an access terminal that has the ability to demodulate a portion of the bandwidth at any given time may only be needed to monitor a subset of bandwidth 400 corresponding to one carrier 402. Alternatively, one access terminal may be assigned to any number of carriers 402 less than all of the carriers 402 in the bandwidth. In one example, forward link control channel 406 so that an access terminal operating on a given carrier 402 can be supported by control channels 406 and 440 of that carrier without reference to information contained in other carriers. And by ensuring that the reverse link control channel 440 contains sufficient information for each carrier, single carrier transmission may be supported. The required support may be provided by including equivalent channel information in the forward link control channel 406 and reverse link control channel 440 of each carrier 402. Thus, according to one aspect, one or more of acquisition, allocation, access, request, power control, pilot, and reporting channels may be present on each of the carriers 402. These channels may be provided, for example, in a superframe preamble (eg, superframe preamble 312) and forward link control channel 406 and / or reverse link control channel 440 for one carrier 402. May be included. However, each carrier 402 may provide the above channels, but the actual coding, transmission rate, message type and timing, resource allocation, overhead messaging, hop pattern and / or sequence, and It should be appreciated that other transmission and assignment parameters may vary for different carriers 402. Further, the format, transmission rate, and / or hopping information may be signaled to the access terminal by a separate control channel that is not associated with a particular carrier 402 and / or by other means, or It may be usable in other ways.

  In other instances, one or more terminals with greater ability to demodulate signals may have two or more carriers in one superframe in consecutive superframes or during a communication session. May be scheduled. Further, such terminals may be able to utilize different carriers 402 for reverse link frame 408 and forward link frame 404 during a communication session or superframe. Such terminals may be scheduled on different carriers in different superframes or during communication sessions. Additionally and / or alternatively, such terminals may be scheduled in frames that are substantially synchronized in time on different carriers 402. Such multi-carrier access terminals are scheduled to provide resource load balancing for a given carrier 402 and to provide statistical multiplexing gains over the entire bandwidth 400. May be.

  In order to support multi-carrier access terminals that operate across several carriers 402, several approaches may be utilized. In a first example, a multi-carrier access terminal may demodulate the superframe preamble and forward link control channel 406 for each of the carriers 402 on which the terminal operates individually. Thus, all allocation, scheduling, power control, and other suitable operations can be performed on carriers on a carrier-by-carrier basis. In a second example, a separate control channel may include operating parameters for each carrier 402 so that the access terminal can use one or more of the carriers operated by the separate control channel. To obtain information on the superframe preamble and forward link control channel 406 for. Further, the additional control channel modulates and decodes one or more of the superframe preamble, forward link control channel 406, and reverse link control channel 440 for one or more carriers 402. May be included. Accordingly, the superframe preamble, forward link control channel 406, and / or reverse link control channel 440 for a given carrier 402 can be decoded at any point in time.

  In the third example, information for all carriers 402 or groups of carriers 402 is maintained in a single carrier 402 superframe preamble, forward link control channel 406, and / or reverse link control channel 340. May be. In this example, an access terminal that can utilize multiple carriers in a communication session may receive control information from a single carrier and transmit control information on the same carrier or different carriers. According to one aspect, the carrier utilized for this functionality may change in time according to a predetermined sequence or other means. In a fourth example, assignments for scheduling purposes may constitute multiple assignments from different carriers 402. Thus, the access terminal receives individual assignments for multiple carriers 402 and then complete assignments for frames that may or may not overlap in time for both the forward and reverse links. These assignments may be combined to determine

  In a particular non-limiting example, bandwidth 400 may be 20 MHz, and each carrier 402 may comprise 5 MHz of bandwidth 400. Further, each carrier 402 may include 512 subcarriers. However, it should be appreciated that other bandwidth 400 sizes, carrier 402 sizes, and / or the number of subcarriers for carrier 402 may be utilized. For example, the carrier 402 may include a bandwidth of 1.25 MHz and 128 subcarriers. Alternatively, the carrier 402 may include 2.5 MHz of bandwidth and 256 subcarriers. Further, the number of assigned subcarriers may vary between carriers 402. The size of the carrier 402 can be subject to applicable bandwidth allocation and its division from the applicable regulatory entity in the system. Further, one or more carriers 402 may be synchronized with each other to have different start and / or end times for forward link frame 404 and / or reverse link frame 408. It should be recognized that it is good. In such cases, signaling or assignment messages provided by control channel 406 and / or superframe preamble may communicate timing information for carrier 402.

  According to one aspect, one or more effective subcarriers of OFDM on carrier 402 can be designated as guard subcarriers and no energy is transmitted on the designated subcarriers. May not be modulated. In one instance, the superframe preamble and the number of designated guard subcarriers in each frame may be given by one or more messages in the forward link control channel 406 and / or the superframe preamble. . According to other aspects, packets may be jointly coded for multi-carrier access terminals to reduce overhead transmission to the terminals. This may be done, for example, even though the packet symbols should be transmitted on different carrier 402 subcarriers. In this way, a single cyclic redundancy check may be utilized for one or more packets, and transmissions on several carriers 402 that contain symbols from the packet may be an overhead of cyclic redundancy check. It can be made not to receive overhead transmissions. Alternatively, the access point may modulate that packet on a per-carrier basis by including only symbols to be transmitted on a given carrier 402 in a given packet. In one example, the access point may further bundle certain carriers 402 for packet modulation purposes. For example, the access point may modulate together symbols from the top two carriers 402 in a single packet.

  Further, it should be appreciated that the scheduler for each of the carriers 402 may utilize a uniform or non-uniform approach for hopping. For example, a different channel tree or hop permutation may be used for each carrier 402. Further, each carrier 402 may be scheduled according to uniform or non-uniform techniques and algorithms. For example, each carrier 402 has a channel tree and structure as described in copending US patent application Ser. No. 11 / 261,837 filed Oct. 27, 2005, which is hereby incorporated by reference in its entirety. May be included.

  FIG. 5A illustrates a forward link frame structure 502 for a multiple access wireless communication system, eg, according to various aspects. In one example, forward link frame 502 may be divided into one control channel 510 and one or more data channels 522. According to one aspect, the control channel 510 can include continuous or discontinuous groups of subcarriers. Furthermore, a variable number of subcarriers can constitute the control channel 510. The number of subcarriers making up the control channel 510 may be allocated depending on the desired amount of control data and / or other suitable aspects. According to another aspect, the data channel 522 can be generally used for data transmission.

  In one example, control channel 510 may include one or more signaling channels 512-518. Signaling channels 512-518 are shown in forward link frame 502 as being multiplexed in time, while signaling channels 512-518 are different orthogonal, quasi-orthogonal, or scramble codes, and It may be multiplexed using (or) any combination of time, code, and frequency. In one example, signaling channels 512-518 may include one or more pilot channels 512 and / or 514. In a non-limiting example where forward link frame 502 is utilized in a symbol rate hopping mode (eg, symbol rate hopping mode 722), pilot channels 512 and / or 514 are forward It may be present on the OFDM symbol in link frame 502. Thus, in such instances, pilot channels 512 and / or 514 may not be present on control channel 510. In other examples, control channel 510 may include one or more of signaling channel 516 and power control channel 518. In one example, signaling channel 516 may include assignments, acknowledgments, and / or power references, and adjustments for data, control, and pilot or transmission on the reverse link. . Further, power control channel 518 is information regarding interference generated at various sectors (eg, sector 104 of system 100) in a wireless communication system due to transmission from an access terminal (eg, terminal 120) in one sector. Can be included.

  In certain non-limiting examples, power control channel 518 may exist only on a single carrier (eg, carrier 402). In this example, all single carrier access terminals can be scheduled on a scheduled carrier, while multi-carrier access terminals can be tuned to a scheduled carrier for power control. . Thus, according to one aspect, a single power reference can be utilized. Also, in such an aspect, the multi-carrier access terminal can transmit it between different frames over time so that the reverse link control channel is not simply transmitted on the same frequency as the reverse link data transmission. It is possible to hop a reverse link control channel (eg, reverse link control channel 440). In this case, to adjust the transmission power of the multi-carrier access terminal across all carriers to allow uniform power control across all carriers for reverse link transmissions by that multi-carrier access terminal In addition, a single reference may be utilized for the multicarrier access terminal. Alternatively, a multi-carrier access terminal may require multiple power control loops, one for each carrier or group of carriers that have a common power control channel. In this case, transmission on a single carrier or a group of carriers may be performed on an individual basis. Further, different power references and / or back-offs may be utilized for each carrier or group of carriers.

  In accordance with another aspect, forward link frame 502 can further include subcarrier 520 at the edge of the bandwidth allocated to forward link frame 502. These subcarriers 502 may function as, for example, quasi-guard subcarriers. According to one or more of the above aspects, if multiple transmit antennas (eg, at base station 110 and / or terminal 120) can be used to transmit to one sector, the It should be appreciated that each of the transmit antennas may share a common superframe timing, superframe index, OFDM symbol feature, and / or hop sequence. Furthermore, it should be appreciated that the control channel 510 may comprise the same assignment as data transmission in one or more aspects. For example, if one or more data transmissions utilize block hopping (eg, by block hopping mode 320), a similar or dissimilar sized block is allocated for control channel 510. Also good.

  FIG. 5B illustrates an example reverse link frame structure 504 for a multiple access wireless communication system in accordance with various aspects. In one example, reverse link frame 504 is similar to forward link frame in that control channel 530, one or more data channels 542, and one or more edge subcarriers 540. Can be included. In other instances, the data channel 542 may be in block hopping mode (eg, block hopping mode 720) or symbol rate hopping mode (eg, symbol rate hopping) in a given reverse link frame 504. The hopping mode 722) can be operated. Further, the data channel may operate according to a single mode in different reverse link frames 504 or according to different modes for different reverse link frames 504. Further, the control channel 530 can be comprised of signaling channels 532-538 that can be multiplexed in time as shown in the reverse link frame 504. Alternatively, signaling channels 532-538 may be multiplexed using different orthogonal, quasi-orthogonal, or scrambling codes, different frequencies, and / or any combination of time, code and frequency.

  In one example, signaling channels 532-538 in control channel 530 can include pilot channel 532. Pilot channel 532 can include a pilot that, in one example, can cause an access point (eg, base station 110) to evaluate the reverse link. The control channel 530 also includes a request channel 534 that can include information for requesting resources for the forward link frame 502 and / or reverse link frame 504 arriving at the access terminal (eg, terminal 120). May be included.

  In other examples, the control channel 530 can include a reverse link feedback channel 536 that allows one or more terminals to provide feedback for channel information (CQI). In one example, the CQI provided by one access terminal to the reverse link feedback channel may be one or more scheduled modes and / or scheduling for transmission to that access terminal. Can be related to available modes. By way of example, modes in which CQI can be involved include beamforming, SDMA, precoding, and / or any suitable combination thereof. In other examples, the control channel 530 may be a reference for generating power control instructions for one or more reverse link transmissions (eg, data transmission and / or signaling transmission) by the access terminal. It can further include a power control channel 538 that can be used as In one example, one or more feedback channels 536 can be included in the power control channel 538.

  With reference to FIGS. 6-11, illustrated are methods for signal acquisition in a wireless communication network. For simplicity of explanation, the methods are illustrated and described as a series of acts, but according to one or more embodiments, several acts are illustrated and described herein. It should be understood and appreciated that the methods are not limited by the order of actions, as they may occur in a different order and / or concurrently with other acts. For example, those skilled in the art will understand and appreciate that a method could alternatively be presented as a series of interrelated states or events, such as in a state diagram. Moreover, not all illustrated acts may be required to implement a methodology in accordance with one or more embodiments.

  With reference to FIG. 6, illustrated is a methodology 600 for transmitting acquisition information in a wireless communication system (eg, system 200). Method 600 may be performed, for example, by an access point (eg, access point 210) and / or an antenna group within the access point (eg, antenna group 212). The method 600 begins at block 602 where a system bandwidth (eg, bandwidth 400) is divided into multiple carriers (eg, carrier 402). Next, an access terminal (eg, access terminal 220) is assigned to one or more of the plurality of carriers in block 604. Method 600 ends at block 606 where acquisition information is transmitted to an access terminal using an acquisition channel associated with the assigned carrier. The acquisition channel can be included, for example, in the forward link control channel associated with the assigned carrier. Further, the acquisition information may include one or more acquisition pilots, a primary broadcast channel, and / or a secondary broadcast channel.

FIG. 7 illustrates a method 700 for generating and transmitting acquisition information in a wireless communication system (eg, system 200). Method 700 may be performed, for example, by a base station and / or an antenna group within the base station. Method 700 begins at block 702 where symbols for a superframe preamble (eg, superframe preamble 312) are provided. The provided symbols can include, for example, acquisition information, other sector interference information, pilots, and / or other suitable information based on a particular system design. The method 700 proceeds to block 704 where a carrier for transmitting a superframe preamble is assigned. In one example, this assignment can be based on a hop sequence, pattern, or other predetermined assignment scheme. For example, each access point and / or sector in the system may be assigned a specific pseudo-noise (PN) sequence that uniquely identifies neighboring access points and / or access points or sectors in the sector. Further, to reduce the required computation for signal acquisition, all available PN sequences for the system can be arranged in M ₁ sets, each containing M ₂ PN sequences. The PN sequence assigned to a particular access point and / or sector may be embedded in an algorithm that may determine carrier assignment at block 704. In one example, the algorithm used may change over time. For example, the algorithm may change after a number of uses equal to the number of PN sequences in which it is used or other predetermined number of uses.

  In other examples, the access point identification may be transmitted as part of the acquisition signal, which may be part of a superframe preamble to which a carrier is assigned at block 704. The access terminal uses this identification to scramble one or more received pilots, to identify the access point from which the transmission is received, and / or to perform other appropriate actions. Also good. Additionally and / or alternatively, each access point may use an access point or sector to enable the access terminal to perform signal acquisition efficiently by using a Walsh-Hadamard transform. The acquired signal can be spread over one or more carriers assigned at block 704 according to uniquely identified Walsh sequences. Upon completion of the act described in block 704, the method ends at block 706 where an inverse Fourier transform is performed to provide time domain samples for a predetermined number of subcarriers. . The predetermined number of subcarriers used in block 706 may be equal to some or all of the carrier subcarriers allocated in block 704.

  FIG. 8 illustrates a method 800 for generating and transmitting acquisition information in a wireless communication system (eg, system 200). The method 800 may be performed, for example, by a base station and / or an antenna group within the base station. Method 800 begins at block 802 where symbols for a superframe preamble are provided. The provided symbols can include, for example, acquisition information, other sector interference information, pilots, and / or other suitable information based on a particular system design. The method 800 then proceeds to block 804 where information is assigned to a group of subcarriers or tones that include all or a portion of the carriers on which a superframe preamble can be transmitted.

  In one example, this assignment can be based on a hop sequence, pattern, or other predetermined assignment scheme. For example, each access point and / or sector in the system may be assigned a specific pseudo-noise (PN) sequence that uniquely identifies the access point or sector among neighboring access points and / or sectors. The PN sequence assigned to a particular access point and / or sector may be embedded in an algorithm that can determine the subcarrier assignment at block 804. In one example, the algorithm used may change over time. For example, the algorithm may change after a number of uses equal to the length of the PN sequence for which the algorithm is used, or other predetermined number of uses. Upon completion of the act described at block 804, the method ends at block 806, where an inverse Fourier transform is provided to provide time domain samples for a predetermined number of subcarriers. (IFFT) is executed. The predetermined number of subcarriers used at block 806 may be equal to some or all of the subcarriers of the carriers assigned at block 804.

  With reference to FIG. 9, illustrated is a methodology 900 for communicating on one or more carriers (eg, carrier 402) in a wireless communication system (eg, system 200). Method 900 can be performed, for example, by a terminal (eg, access terminal 220). Method 900 begins at block 902 where a search is performed over available system bandwidth (eg, bandwidth 400) for acquired information from an access point (eg, access point 210). Alternatively, the acquisition information may be received from an antenna group (eg, antenna group 212) within the access point. In one example, the search at block 902 is performed over all available system bandwidth. Alternatively, the search in block 902 may be performed over one or more predetermined carriers within the system bandwidth.

  Next, the method 900 proceeds to block 904 where one or more assigned carriers are based at least in part on the received acquisition information for communication with the access point and / or antenna group. Determined. In one example, the acquired information is received as a result of a search performed at block 902. Further, the received acquisition information may be received on a single carrier within the system bandwidth. In this illustration, the one or more carriers assigned at block 904 may or may not include the carrier from which the acquisition was received. Upon completion of the act described at block 904, method 900 ends at block 906, where one or more of the carriers assigned at block 904 are used to communicate with the access point.

  FIG. 10 illustrates a method 1000 for obtaining information for communication in a wireless communication system (eg, system 200). Method 1000 may be performed by a terminal, for example. The method 1000 begins at block 1002, where an attempt is made to sense the acquired signal over all or substantially all of the available system bandwidth. In one example, the acquisition signal may be transmitted by a base station and / or antenna group as part of a superframe assembly (eg, superframe assembly 312). Further, the acquisition signal may span all or substantially all of one carrier (all except guard subcarriers 520 and / or 540). If an acquisition signal is detected, method 1000 proceeds to block 1002, where a carrier is determined based on the position of the subcarrier from which the acquisition signal was received. The method 1000 then proceeds further to block 1006 where the location of the superframe preamble is determined based on the hop sequence for the incoming frame (eg, frame 314). In one example, the hop sequence can be determined based on the base station identification included in the acquired signal detected at block 1002.

  Method 1000 can then proceed to block 1008 where an access request is communicated based on the carrier determined at block 1004 and / or the superframe preamble determined at block 1006. In one example, this access request may be modulated with an orthogonal or scrambling code that corresponds to whether communication may occur simultaneously on multiple carriers (eg, by a terminal performing method 1000). This orthogonal or scrambling code may be prepared in advance or sent with the acquisition information detected at block 1002.

  In response to the access request communicated at block 1008, an access grant message may be received at block 1010 confirming the access request and / or assigning an initial reverse link subcarrier or block of subcarriers. In one example, the access grant received at block 1010 includes one or more reverse link transmissions (eg, transmissions performed at blocks 1012 and / or 1018) and the reverse link timing of the access point. Timing adjustments can be included that can facilitate alignment. The initial assignment received at block 1010 is also to operate in symbol rate hopping mode (eg, symbol rate hopping mode 322) or block hopping mode (eg, block hopping mode 320). , Instructions for allocation of one or more subcarrier subcarriers to be used for both forward link and reverse link communications, and / or other timing and scheduling parameters. Upon receiving the access grant message at block 1010, the entity performing method 1000 may communicate at block 1012 according to the first assignment received at block 1010.

  Next, one or more supplemental assignments may be assigned at block 1014. It should be appreciated that the act described in block 1014 is optional and need not be performed in connection with method 1000. Accordingly, method 1000 may proceed to block 1016 after block 1012 or 1014, where a second assignment of reverse link subcarriers is received. In one example, if it is established at block 1006 that communications can occur simultaneously on multiple carriers, the second assignment received at block 1016 includes a change carrier message. And the carrier to which the next or current assignment falls can be identified. Alternatively, the change carrier message may be sent independently of those assignments prior to the second assignment received at block 1016 and / or any supplemental assignments received at block 1014. Further, the change carrier message may be transmitted on the forward link as one or more data packets. The data packet may be verified by the entity performing method 1000 to indicate that the change carrier message has been demodulated. In another alternative, the access grant received at block 1000 may include change carrier information. This information may be provided on an initial basis or on a carrier-by-carrier basis if each carrier is accessed separately.

  According to one aspect, the second assignment received at block 1016 may include multiple assignments for different carriers that can be individually decoded. Alternatively, the second assignment may include a joint assignment for more than one carrier received by a single carrier. According to other aspects, information regarding carrier timing and other characteristics may be provided with a second assignment to improve operation for newly scheduled carriers. If one or more data packets are used to send a change carrier message, those data packets may contain certain parameters for the newly scheduled carrier and additional resources Can provide information for proper communication on new carriers. Alternatively, each carrier has one piece of information to allow demodulation of a superframe preamble and / or other carrier's control channel to allow communication on other carriers, or other suitable information. Or it may be included in more superframes or control channels (eg, control channels 406 and / or 440). In addition, a separate message including parameters for the new carrier may be received (eg, on control channel 406 and / or 440 for the carrier). If a second assignment is received at block 1016, method 1000 ends at block 1018 where communication is terminated according to the second assignment. In one example, if the acquired information corresponding to the assigned carrier cannot be demodulated properly (eg, at block 1004), the implementation of method 1000 can be tuned to other carriers. .

  FIG. 11 illustrates a method 1100 for obtaining information for communication in a wireless communication system (eg, system 200). Method 1100 may be performed by a terminal, for example. The method 1100 begins at block 1102, where in one example where an attempt is made to detect acquired information over all or substantially all of the available system bandwidth, the acquired information may be the base station and / or ) May be transmitted by an antenna group as part of a superframe preamble (eg, superframe preamble 312). Further, the acquisition signal may span all or substantially all of the carrier (all except guard subcarriers 520 and / or 540). If an acquisition symbol is detected at block 1102, the method proceeds to block 1104 where the sector in which the acquisition signal was transmitted (eg, sector 104) is assigned to the carrier or superframe preamble used for the acquisition signal on the carrier. It is determined based on the position of a larger group of subcarriers to be selected. In one example, the sector determined at block 1104 may correspond to an antenna group in the base station of the system. Further, the sector may be determined in step 1104, at least in part, by determining an identifier for the sector, such as a sector ID. Finally, the method 1100 ends at block 1106 where broadcast information is acquired on the first broadcast channel and / or the second broadcast channel. However, the act described in block 1106 is optional and may be omitted, for example, if there is a sticky assignment or if an entity performing method 1100 is already scheduled. It should be recognized that

  Referring now to FIG. 12, a block diagram illustrating an example wireless communication system 1200 in which one or more embodiments described herein can function is provided. In one example, system 1200 is a multiple-input, multiple-output (MIMO) system that includes a transmitter system 1210 and a receiver system 1250. However, the transmitter system 1210 and / or the receiver system 1250 may, for example, have multiple transmit antennas (e.g., on a base station) transmit one or more symbol streams to a single antenna device (e.g., mobile It should be recognized that it can also be applied to multi-input, single-output systems that can transmit to a station). Further, it should be appreciated that the transmitter system 1210 and / or receiver system 1250 aspects described herein can be utilized in connection with a single output, single input antenna system.

  According to one aspect, traffic data for a number of data streams is provided from a data source 1210 to a transmit (TX) data processor 1214 at a transmitter system 1210. In one example, each data stream may be transmitted by each transmit antenna 1224. In addition, TX data processor 1214 formats and encodes traffic data for each data stream based on the particular encoding scheme selected for the data stream that it writes to provide the encoded data. , And can be interleaved. In one example, the coded data for each data stream may be multiplexed with pilot data using OFDM techniques. The pilot data may be, for example, a known data pattern that is processed in a known manner. Further, the pilot data may be used at receiver system 1250 to evaluate channel response. At transmitter system 1210, the multiplexed pilot and coded data for each data stream is transmitted to a particular modulation scheme (eg, BPSK, QSPK, M, etc.) selected for each data stream to provide modulation symbols. -PSK, or M-QAM) can be modulated (i.e., symbol mapped). In one example, the data rate, coding, and modulation for each data stream may be determined by instructions performed by processor 1230 and / or provided by processor 1230.

[0001] Next, modulation symbols for all data streams can be provided to a TX processor 1220, which may further process the modulation symbols (eg, for OFDM).
The modulation symbols for all data streams may then be provided to TX processor 1220, which may further process the modulation symbols (eg, for OFDM). TX MOMO processor 1220 may provide modulation symbol streams _{N T N T} transmitters (TMTR) to 1222A～1222t. In one example, each transmitter 1222 can receive and process each symbol stream to provide one or more analog signals. Each transmitter 1222 can further condition (eg, amplify, filter, upconvert) its analog signal to provide a modulated signal suitable for transmission on a MIMO channel. Thus, the modulation signal of _{N T} from transmitters 1222a~1222t may be transmitted from the antenna 1224a~1224t of _{N T,} respectively.

According to another aspect, the modulation signal to be transmitted may be received by an antenna 1252a~1252r of _{N R} at the receiver Shishitemu 1250. The received signal from each antenna 1252 can be provided to each receiver (RCVR) 1254. In one example, each receiver 1254 can adjust (eg, filter, amplify, and downconvert) each received signal and digitally convert the adjusted signal to provide samples. And process those samples to provide a corresponding “received” symbol stream. RX MIMO / data processor 1260, the N _T "is detected," ( "detected") the N _R from the receiver 1254 of the N _R based on a particular receiver processing technique to provide a symbol stream A received symbol stream can be received and processed. In one example, each detected symbol stream can include symbols that are estimates of the modulation symbols transmitted for the corresponding data stream. RX processor 1260 demodulates, deinterleaves, and decodes each detected symbol stream, at least in part, to recover the traffic data for the corresponding data stream. -The stream can be processed. Accordingly, the processing by RX data processor 1218 may be complementary to the processing performed by TX MIMO processor 1220 and TX data processor 1214 at transmitter system 1210.

  In other instances, RX processor 1260 may be limited in the number of subcarriers it can simultaneously demodulate. For example, the RX processor 1260 may be limited to 512 subcarriers at 5 MHz, 128 subcarriers at 1.25 MHz, or 256 subcarriers at 2.5 MHz. This limitation can be defined, for example, by the sample rate at which the RX processor 1260 can operate, the memory available for the FFT, and / or other functions available for demodulation, the FFT range of the RX processor 1260. It may be a function of The cost of the receiver system 1250 can increase as the number of subcarriers utilized increases. According to one aspect, channel response estimation generated by RX processor 1260 may be used to perform space / time processing at the receiver, adjust power levels, change modulation rate or scheme, and / or. It can be used for other suitable operations. Further, RX processor 1260 may further estimate channel characteristics such as, for example, signal to noise and interference ratios (SNRs) of the detected symbol stream. RX processor 1260 can provide estimated channel characteristics to processor 1270. In one example, RX processor 1260 and / or processor 1270 can further obtain an estimate of the “operating” SNR for the system. The processor 1270 can provide channel state information (CSI) that can comprise information regarding the communication link and / or the received data stream. This information may include, for example, the operating SNR. CSI may be processed by TX data processor 1278, modulated by modulator 1280, adjusted by transmitters 1254a-1254r, and transmitted to transmitter system 1210.

  At transmitter system 1210, the modulated signal from receiver system 1250 is received by antenna 1224, conditioned by receiver 1222, demodulated by demodulator 1240, and recovered CSI reported by receiver system 1250. Can be processed by an RX data processor. In one example, the reported CSI is provided to processor 1230 and to determine the data rates and coding and modulation schemes to be used for one or more data streams. Can be used. The determined coding and modulation scheme may be provided to transmitter 1222 for quantization and / or for use in subsequent transmissions to receiver system 1250. Additionally and / or alternatively, the reported CSI may be used by processor 1230 to generate various controls for TX data processor 1214 and TX MIMO processor 1220.

In one example, processor 1230 at transmitter system 1210 and processor 1270 at receiver system 1250 direct the operation at each of those systems. Further, memory 1232 at transmitter system 1210 and memory 1272 at receiver system 1250 can provide storage for program codes and data used by processors 1230 and 1270, respectively. Further, at receiver system 1250, various processing techniques may be used to process the _NR received signals to indicate the _NT transmitted symbol streams. These receiver processing techniques are also referred to as spatial and space-time receiver processing techniques, which may also be referred to as equalization techniques, and / or “continuous dry” or “continuous cancel” receiver processing techniques. “Successive nulling / equalization and interference cancellation” receiver processing techniques may be included.

  FIG. 13 is a block diagram of a system 1300 that coordinates the generation and transmission of acquired information in accordance with various aspects described herein. In one example, system 1300 includes a base station or access point 1302. As shown, access point 1302 receives signals from one or more access terminals 1304 via receive (Rx) antenna 1306 and one or more access terminals 1304 via transmit (Tx) antenna 1308. Can be sent to.

  Further, access point 1302 can comprise a receiver 1310 that receives information from receive antenna 1306. In one example, receiver 1310 can be operatively associated with a demodulator (Demod) 1312 that demodulates received information. Demodulated symbols can be analyzed by processor 1314. The processor 1314 may include code clusters, access terminal assignments, associated lookup tables, information associated with unique scrambling sequences, and / or other suitable types. Coupled to a memory 1316 capable of storing information. In one example, the access point 1302 can use the processor 1314 to perform the methods 600, 700, 800, and / or other suitable methods. Access point 1302 may also include a modulator 1318 that can multiplex a signal for transmission by a transmitter 1320 via transmit antenna 1308 to one or more access terminals 1304.

  FIG. 14 is a block diagram of a system 1400 that coordinates signal acquisition in a wireless communication environment in accordance with various aspects described herein. In one example, system 1400 includes an access terminal 1402. As shown, the access terminal 1402 can receive signals from one or more access points 1404 and transmit to one or more access points 1404 by the antenna 1408. Further, access terminal 1402 can comprise a receiver 1410 that receives information from antenna 1408. In one example, receiver 1410 can be operatively associated with a demodulator (Demod) that demodulates received information. Demodulated symbols can be analyzed by processor 1414. The processor 1414 can be coupled to a memory 1416 that can store data and / or program code associated with the access terminal 1402. Further, access terminal 1402 can use processor 1414 to perform methods 900, 1000, 1100, and / or other suitable methods. Access terminal 1402 may also include a modulator 1418 that can multiplex a signal for transmission by a transmitter 1420 via antenna 1408 to one or more access points 1404.

  FIG. 15 illustrates an apparatus 1500 that facilitates transmission of acquired information in a wireless communication system (eg, system 200). It should be appreciated that apparatus 1500 is presented including functional blocks that can be functional blocks representing functions performed by a processor, software, or combination thereof (eg, firmware). Apparatus 1500 can be implemented in connection with an access point (eg, access point 210) and to divide system bandwidth (eg, bandwidth 400) into multiple carriers (eg, carrier 402) 1502. Can be assembled. In one example, apparatus 1500 can use a module for assigning an access terminal (eg, access terminal 220) to one or more carriers 1502 and the acquired information using one or more carriers 1506. May further include a module for transmitting to.

  FIG. 16 illustrates an apparatus 1600 that facilitates communication in a wireless communication system (eg, system 200). It should be appreciated that apparatus 1600 is presented with functional blocks that can be functional blocks that represent functions performed by a processor, software, or combination thereof (eg, firmware). Apparatus 1600 can be implemented in connection with an access point (eg, access point 220) and searches for acquired information from an access point (eg, access point 210) over a system bandwidth (eg, bandwidth 400). Modules may be included. In one example, a module for determining one or more assigned carriers (eg, carrier 402) and one or more assigned carriers 1606 for communication with access point 1604 is used. And a module for communicating with the access point.

  It is to be understood that the embodiments described herein can be implemented by hardware, software, firmware, middleware, microcode, or any combination thereof. If the system and / or method is implemented in software, firmware, middleware or microcode, program code or code segments, they are stored in a machine readable medium such as a storage component. It may be stored. A code segment may represent a procedure, function, subprogram, program, routine, subroutine, module, software package, class, or any combination of instructions, data structure, or program statement . A code segment may be coupled to another code segment or a hardware circuit by sending and / or receiving information, data, arguments, parameters, or memory contents. Information, arguments, parameters, data, etc. can be obtained using any suitable means including memory sharing, message passing, token passing, network transmission, etc. It can be sent, forwarded or transmitted.

  For software implementation, the techniques described herein may be implemented with modules (eg, procedures, functions, and so on) that perform the functions described herein. The software code can be stored in a memory unit and executed by a processor. The memory unit may be implemented within or outside the processor, and in either case it may be communicatively coupled to the processor by various means known in the art.

  What has been described above includes examples of one or more embodiments. Of course, it is not possible to describe every conceivable combination of components or methods for the purpose of describing the above embodiments, but those skilled in the art will recognize many other combinations and permutations of various embodiments. Can be recognized as possible. Accordingly, the described embodiments are intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims. Further, as long as the term “comprising” is used in the detailed description or in the claims, this term is used as a transition term in the claims, just as the term “comprising” is interpreted. It is intended to be comprehensive. Furthermore, the term “or” as used in the detailed description or claims means “non-exclusive OR”.

1 illustrates a wireless multiple-access communication system in accordance with various aspects presented herein. 1 is a block diagram of a system that facilitates signal acquisition in a wireless communication environment in accordance with various aspects described herein. 1 illustrates an example superframe structure for a multiple access wireless communication system in accordance with various aspects. 1 illustrates an example superframe structure for a multiple access wireless communication system in accordance with various aspects. 1 illustrates an example channel structure for a multiple access wireless communication system in accordance with various aspects. 1 illustrates an exemplary forward link frame structure for a multiple access wireless communication system. 1 illustrates an exemplary reverse link frame structure for a multiple access wireless communication system. 2 is a flow diagram of a method for transmitting acquisition information in a wireless communication system. 2 is a flowchart of a method for generating and transmitting acquisition information in a wireless communication system. 2 is a flowchart of a method for generating and transmitting acquisition information in a wireless communication system. 2 is a flow diagram of a method for communicating on one or more carriers in a wireless communication system. 2 is a flowchart of a method for obtaining information for communication in a wireless communication system. 2 is a flowchart of a method for obtaining information for communication in a wireless communication system. 1 is a block diagram illustrating an example wireless communication system in which one or more embodiments described herein may function. FIG. FIG. 10 is a block diagram of a system that coordinates generation and transmission of acquired information in accordance with various aspects. FIG. 11 is a block diagram of a system that coordinates signal acquisition in a wireless communication environment in accordance with various aspects. FIG. 11 is a block diagram of an apparatus that facilitates transmission of acquired information in a wireless communication system in accordance with various aspects. FIG. 11 is a block diagram of an apparatus that facilitates transmission of acquired information in a wireless communication system in accordance with various aspects.

Claims (44)

Generating multiple symbols of the acquired signal;
Allocating the transmission of the acquisition signal to a certain number of subcarriers equal to all or less than one or more carrier bandwidths,
A method for generating and transmitting acquisition information in a wireless communication system.   The method of claim 1, wherein the one or more carriers are selected from a plurality of carriers, and the plurality of carriers correspond to a substantially non-overlapping portion of bandwidth.   The method of claim 2, wherein the plurality of carriers comprises substantially all available bandwidth in the wireless communication system.   The method of claim 2, wherein the plurality of carriers comprises substantially all available bandwidth in a sector of the wireless communication system.   3. The method of claim 2, wherein each of the one or more carriers comprises 512 subcarriers and 5 MHz bandwidth.   3. The method of claim 2, wherein the one or more carriers comprise 256 subcarriers and 2.5 MHz bandwidth.   3. The method of claim 2, wherein the one or more carriers comprise 128 subcarriers and a bandwidth of 1.25 MHz.   The plurality of carriers are seven used carriers and one unused carrier, and assigning transmission of the acquisition signal is performed according to a predetermined frequency reuse plan for the seven used carriers. 3. The method of claim 2, comprising assigning transmission of the acquired signal to all or fewer than all of the subcarriers in one of the utilized carriers.   The plurality of carriers are seven carriers, and assigning transmission of the acquisition signal is all or all of the subcarriers in one of the seven carriers according to a predetermined frequency reuse plan for the seven carriers. 3. The method of claim 2, comprising assigning transmissions of the acquisition signal to fewer subcarriers.   The method of claim 1, wherein the acquisition signal includes information regarding at least one broadcast channel.   The method of claim 1, wherein assigning the acquisition signal transmission comprises assigning the acquisition signal transmission to a number of subcarriers based at least in part on a hop sequence.   The method of claim 1, further comprising transmitting the acquisition signal to an access terminal on the assigned carrier.   13. The method of claim 12, wherein allocating transmission of the acquisition signal includes transmitting the acquisition signal in a superframe preamble. Scheduling one or more carriers to be used for communication with the access terminal;
13. The method of claim 12, further comprising communicating with the access terminal using one or more of the scheduled carriers. Scheduling the one or more carriers is
Receiving an access request from the access terminal;
Scheduling one or more carriers for communication with the access terminal based at least in part on the access request;
15. The method of claim 14, comprising transmitting an assignment for the one or more scheduled carriers to the access terminal.   16. The method of claim 15, wherein the access request received from the access terminal includes an indication of whether the access terminal can communicate on one better carrier.   Scheduling the one or more carriers means scheduling one carrier for communication with the access terminal if the indication is negative and communicating with the access terminal if the indication is positive. 17. The method of claim 16, comprising scheduling a plurality of carriers for. Scheduling a second set of one or more carriers for communication with the access terminal;
Sending a change carrier message to the access terminal including an assignment for the second set of one or more carriers for communication with the access terminal;
16. The method of claim 15, further comprising communicating with the access terminal using one or more scheduled carriers from the second set of carriers. A memory for storing data relating to a plurality of carriers corresponding to a substantially non-overlapping portion of the acquired signal and available system bandwidth;
And a processor configured to allocate transmission of the acquisition signal to all or part of one or more of the plurality of carriers.   20. The wireless communications apparatus of claim 19, wherein the memory further stores data regarding an identification code, and the processor is further configured to assign transmission of the acquisition signal based at least in part on a function of the identification code. .   21. The wireless communication device of claim 20, wherein the identification code is a pseudo noise (PN) sequence.   The wireless communication apparatus according to claim 20, wherein the identification code is a Walsh sequence. Means for dividing available system bandwidth into multiple carriers;
An apparatus for facilitating signal acquisition in a wireless communication network, comprising means for transmitting acquisition information to a terminal using one or more of the plurality of carriers.   24. The apparatus of claim 23, wherein the acquired information includes information regarding at least one broadcast channel.   The means for transmitting the acquisition information includes acquiring the acquisition to one or more of the plurality of carriers based at least in part on a hop sequence for each of one or more of the plurality of carriers. 24. The apparatus of claim 23, including means for assigning a transmission of information. A computer-readable medium having stored thereon computer-executable instructions for generating and transmitting information for acquisition in a wireless communication environment, the instructions comprising:
Dividing the available system bandwidth into a plurality of subcarriers and a plurality of carriers each having a bandwidth equal to a portion of the system bandwidth;
Generating a plurality of symbols for the acquired signal;
A computer readable medium comprising transmitting the acquisition signal on a number of one or more subcarriers in at least one of the plurality of carriers.   27. The computer-readable medium of claim 26, wherein generating the plurality of symbols includes one or more of acquisition information, interference information, and pilot. A processor that executes computer-executable instructions for sending acquisition information, the instructions comprising:
Generating a first acquisition signal and a second acquisition signal;
Transmitting the first acquisition signal to a first access terminal on a carrier comprising a portion of the available system bandwidth;
A processor comprising transmitting the second acquisition signal to a second access terminal on a carrier comprising a portion of available system bandwidth. Receiving a first access request from the first access terminal and a second access request from the second access terminal;
Assigning the first access terminal to a carrier based at least in part on the first access request;
27. The processor of claim 26, further comprising assigning the second access terminal to a plurality of carriers based at least in part on the second access request.   The first access terminal is assigned to a carrier based on information in the first access request indicating that the first access terminal cannot communicate on a plurality of carriers, and the second access terminal is 30. The processor of claim 29, assigned to multiple carriers based on information in the second access request indicating that the second access terminal can communicate on multiple carriers. A method for obtaining information for communication in a wireless communication system, comprising:
Attempting to detect the acquired signal on at least two carriers each comprising one or more subcarriers and a portion of the available system bandwidth;
Determining a future carrier on which information is communicated by an access point based at least in part on the carrier on which the acquired signal is detected.   32. The method of claim 31, wherein each carrier comprises 512 subcarriers and 5 MHz bandwidth.   32. The method of claim 31, wherein each carrier comprises 256 subcarriers and a 2.5 MHz bandwidth.   32. The method of claim 31, wherein each carrier comprises 128 subcarriers and a bandwidth of 1.25 MHz.   32. The method of claim 31, wherein determining the future carrier comprises determining a future carrier on which information is communicated based at least in part on a hop sequence. A memory for storing data on a plurality of carriers;
A processor configured to attempt to detect acquired signals on the plurality of carriers and to determine a future carrier on which information is communicated by the sector based at least in part on the carrier on which the acquired signal is detected A wireless communication device comprising:   38. The wireless communications apparatus of claim 36, wherein the processor is further configured to determine a future carrier based at least in part on a hop sequence.   38. The wireless communications apparatus of claim 37, wherein the acquisition signal includes an identifier for the sector and the hop sequence is a function of an identifier for the sector.   40. The wireless communications apparatus of claim 38, wherein the identifier for the sector is a pseudo noise (PN) sequence.   40. The wireless communications apparatus of claim 38, wherein the identifier for the sector is a Walsh sequence. Means for detecting an acquired signal with a system bandwidth corresponding to a plurality of carriers;
An apparatus for facilitating signal acquisition in a wireless communication network comprising: means for determining a carrier for communication with an access point based at least in part on a carrier on which the acquisition signal is detected. A computer-readable medium having stored thereon computer-executable instructions for obtaining information for communication in a wireless communication environment, the instructions comprising:
Sensing an acquired signal transmitted by the access point over a bandwidth equal to at least two carriers;
A computer readable medium comprising determining a carrier for communication with the access point based at least in part on the acquired signal. A process for executing computer-executable instructions for communicating in a wireless communication system, the instructions comprising:
Receiving a signal transmitted from a sector of the wireless communication system;
Determining one or more carriers for communication with the sector based at least in part on the carrier on which the acquisition signal was received;
A processor comprising communicating with the sector at least in part by using one or more carriers determined for the communication. Communicating with the sector is
Transmitting an access request to the sector on one or more carriers determined for the communication;
Receiving from the sector at least one newly allocated carrier for access authorization and communication;
44. The processor of claim 43, comprising communicating with the sector using at least one of the newly allocated sectors for communication.

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